Blue Sapphire
Corundum (Al2O3)
mineral
Category
Organic Gemstone (Not A Rock Or Mineral)
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Not A Rock Or Mineral) in the encyclopedia
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Quartz Geode
Silicon Dioxide (SiO2)
mineral
River-worn Chert
Microcrystalline Quartz (SiO2)
sedimentary
Banded Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
sedimentary
Rose Quartz
Silicon Dioxide (SiO2) with trace titanium, iron, or manganese
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Fossilized Bone / Dinosaur Fossil
Fossilized vertebrate bone (permineralized)
fossil
Quartz
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Brachiopod Fossil in Limestone
Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)
sedimentary
Tiger Iron
Tiger Iron (Hematite, Red Jasper, and Tiger's Eye)
metamorphic
Amber (and Cubic Zirconia)
Fossilized Tree Resin
mineraloid
Coal (likely Bituminous or Lignite)
Organic Sedimentary Rock (Carbonaceous)
sedimentary
Chert (Jasper)
Sedimentary Cryptocrystalline Quartz (SiO2)
sedimentary
Chert Nodule
Chert (Microcrystalline Silicon Dioxide, SiO2)
sedimentary
Clear Quartz / Diamond (untested)
Silicon Dioxide (SiO2) or Carbon (C)
mineral
Amber
Succinite (C10H16O)
gemstone
Yellow Quartz
Silicon Dioxide (SiO2)
mineral
Shale
Shale (clay-sized silicate minerals)
sedimentary
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Dumortierite in Quartz
Silicon Dioxide with Aluminium Borosilicate (SiO2 + (Al,Fe7+)7(BO3)(SiO4)3O3)
mineral
Tumbled banded metamorphic stone
Likely banded gneiss or migmatitic gneiss; exact identification requires testing
metamorphic
Kunzite (Spodumene)
Spodumene (LiAlSi2O6)
mineral
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Lapis Lazuli
Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
metamorphic
Agate
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (primarily SiO2)
metamorphic
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Yellow Chalcedony (Carnelian / Agate Pebbles)
Silicon Dioxide (SiO2)
mineral
Rose Quartz
Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
mineral
Agate (Polished Cabochon Slice)
Silicon Dioxide (SiO2)
mineral
Sandstone Pebble (River Rock)
Sandstone (Quartz-rich sedimentary rock with iron oxide staining)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Banded Agate
Silicon Dioxide (SiO2)
mineral
Variscite in Matrix (often traded as Wardite or Cryptocrystalline Variscite)
Variscite (AlPO4·2H2O)
mineral
Fire Opal in Host Rock
Amorphous Hydrous Silica (SiO2·nH2O)
mineral
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)
sedimentary
Chert / Jasper
Silicon Dioxide (SiO2)
sedimentary
Fossiliferous Limestone containing a Brachiopod or Mollusk Impression
Biogenic Sedimentary Rock / Fossiliferous Limestone
sedimentary
Olivine in Basalt (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4 (Mineral) within Basalt (Rock)
igneous